Zone 7 Water Agency periodically updates its groundwater model to better reflect the hydrogeological understanding of the groundwater basin. Prior to updating the groundwater model, the hydrogeologic conceptual model must be routinely updated to fill data gaps and reflect new data and information. The purpose of this project is to use geophysics to fill data gaps in the existing hydrogeologic conceptual model by collecting subsurface data using geophysical methods, ultimately to be used to update the groundwater model.
This project involves conducting geophysical surveys at 6 project site locations. Seismic Refraction and Electrical Transmissivity Tomography (ERT) surveys will be performed at 3 sites while Transient Electromagnetic (TEM) surveys will be conducted at the remaining sites. Surveys will utilize a series of long cables, probes, electrodes, and recorders.
Surveys do not require soil excavation nor removal of vegetation. Work at each survey line is expected to take 1 to 2 days. The work is expected to take place over about 10 to 14 days in November 2023 through January 2024.
Zone 7 staff are coordinating with the City of Pleasanton, City of Livermore, Livermore Area Recreation and Parks District (LARPD), East Bay Regional Parks, and private landowners to minimize any inconvenience to the public. This includes coordination of survey setup areas, work hours, and public outreach. Some locations are adjacent to residential neighborhoods. The project will abide by all local noise ordinances.